It is a well-known practice to cover the bed portion of a pickup truck with a hood, commonly referred to as a cap, so as to form a closed storage compartment. Such caps are conventionally provided with a rear door which is hinged along the upper edge thereof and, when closed, coacts with the tail gate of the truck for closing the rearward end of the compartment. The cap door normally overlaps the upper edge of the tail gate so that the tail gate cannot be opened so long as the cap door is in a closed and latched condition. To latch the cap door in a closed position, there has been conventionally provided a latching mechanism having a pair of latch bolts disposed adjacent the opposite lower side edges of the door, which latch bolts coact with the adjacent side jams of the cap for holding the door closed. The known latching mechanisms have conventionally been of two types, the first being a deadbolt mechanism employing rigid rods having bolt members rigidly secured to the outer ends thereof and connected to the operating handle whereby activation of the handle was necessary to not only unlatch the door, but also to latch the door. This known deadbolt latching mechanism is preferred by many individuals since it cannot be released due to insertion of a tool or the like between the adjacent edges of the door and tail gate, thereby providing maximum security when the door is closed. However, this deadbolt mechanism is undesirable since it requires manual actuation of the handle in order to latch the door, which operation is normally disliked and in many instances inconvenient.
To avoid the above disadvantage, many individuals prefer to utilize a second type of latching mechanism employing spring-bolts which are automatically cammed inwardly during closing of the door and hence do not require manual actuation of the handle. This known spring-bolt latching mechanism has not, however, provided for maximum security of the compartment when the door is latched since such mechanisms normally utilize flexible elements, such as chains or cables, connected between the bolts and the actuating handle. By insertion of a tool or the like between the adjacent edges of the tail gate and door, these cables can be pulled downwardly so as to retract the bolts, thereby releasing the door and permitting unauthorized access into the compartment. Thus, while the deadbolt and spring-bolt latching mechanisms both possess distinct advantages, each also possess distinct disadvantages which have made the use of both types less than desirable.
A further disadvantage often experienced with the known spring-bolt latching mechanism occurs when the opposite side jams on the cap undergo additional separation after the cap has been installed on the truck, which separation may occur due to the impacts and forces imposed on the truck while traveling over rough highways. The known spring-bolt latching mechanism normally has only a limited bolt travel, such as in the order of one-quarter inch, so that if the side jams move outwardly by this amount, then the bolt release the jams and hence permit undesired and accidental opening of the door. This thus makes the latching mechanism prone to being accidentally released during useage of the truck. This also requires that the cap be installed on the truck with a high degree of accuracy in order to maintain the spacing between the side jams within rather narrow permissible limits.
In addition to the above-mentioned operational disadvantages, the use of two different types of latching mechanisms has also created undesirable problems since manufacturers have to manufacture two different types of latching mechanisms. This accordingly increases the overall cost of the mechanisms and also increases the problem of maintaining adequate inventories of both types. Further, when it is desired to switch from a deadbolt mechanism to a spring-bolt mechanism, or vice versa, such switch requires removal of the prior assembly and mounting of a totally new assembly, which is obviously undesirable both due to the substantial time involved and the necessity of buying a complete new mechanism.
Accordingly, it is an object of the present invention to overcome the above-mentioned disadvantages by providing an improved latching mechanism for a cap door, which mechanism can be easily converted for use as either a deadbolt or a spring-bolt without requiring any timely conversion or expensive replacement of parts.
More particularly, it is an object of this invention to provide an improved latching mechanism, as aforesaid, which utilizes the same basic structure for use as either a spring-bolt or a deadbolt, which structure incorporates a removable fastening element, such as a screw, which can be added to or removed from the structure to permit the mechanism to function as a deadbolt or a spring-bolt, respectively.
A further object of this invention is to provide an improved latching mechanism, as aforesaid, which possesses an improved camming relationship between the spring-bolts and the side jams so as to permit the latching mechanism to successfully operate and maintain a latched relationship with the side jams over a rather large dimensional range, whereby the cap door can be securely latched to the side jams even though the side jams may relatively move outwardly away from one another through a substantial distance either due to faulty installation or due to the application of forces thereon.
A still further object of this invention is to provide an improved latching mechanism, as aforesaid, which provides for increased security of the cap even when the mechanism is used as a spring-bolt since the spring-bolt mechanism possesses features normally previously possessed only by a deadbolt mechanism, thereby effectively preventing unauthorized opening of the door.
Other objects and purposes of the invention will be apparent to persons familiar with structures of this type upon reading the following specifications and inspecting the accompanying drawings.